Halbousi, who had previously served in Iraq's parliament from 2014 to 2017, tallied 169 votes to beat out former defense minister Khalid al-Obaidi's 89 on Saturday, according to lawmaker Husham al-Suhail.
Current Iraqi Vice President Usama al-Nujaifi and former member of parliament Raad al-Dahlaki were also running for the post. A total of 251 lawmakers, out of 329, attended the session and took part in the vote, Presstv Reported.
Announcing the vote, the temporary leader of the assembly Mohammed Ali Zaini said Halbousi, 37, had become the youngest parliament speaker in Iraq's history.
The Iraqi parliament was due to elect a speaker and two deputies during its first meeting on September 3, but failed to do so as parliamentarians were still trying to determine which competing bloc had the most seats.
Lawmakers must next elect a new president and task the leader of the largest bloc to form a government as prime minister.
The country’s main political alliances led by Muqtada Sadr’s Sairoon bloc and the Fatah Alliance led by commander Hadi al-Amiri are expected to cooperate to form a new government.
Incumbent Prime Minister Haider al-Abadi has also announced that he is not seeking to serve a second term in office.
Millions of Iraqis voted on May 12 in their first parliamentary election since the defeat of the Daesh Takfiri terrorist group, but a contentious recount process delayed the announcement of final results until last month.
The Iraqi politics has long been vulnerable to the differences lying along the country’s major ethnic and sectarian fault lines.
Any new government has to move quickly to address the country’s chronic woes, including the poor quality of basic services as well as political and economic mismanagement. It would also have to face the mammoth task of rebuilding the country following three years of struggle against Daesh.